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arXiv · 2606.30057

Quadratic Spaces and Orthogonal Groups over semilocal Rings

Philippe Gille·Erhard Neher
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Abstract

We prove Springer's Odd Degree Theorem for quadratic forms over LG rings, and Scharlau's and Knebusch's norm principles for quadratic forms over semilocal rings. We present applications to the flat cohomology of spin groups and {\'e}tale norm groups.

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Philippe Gille, Erhard Neher. 2026-06-29. Quadratic Spaces and Orthogonal Groups over semilocal Rings. https://arxiv.org/abs/2606.30057

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